It is a common practice to use packet-switched networks, such as IP networks, to connect calls (e.g., voice, data or multimedia calls) between end users. For example, Voice over IP (VoIP) has been developed to permit Customer Premises Equipment (CPE), such as IP telephones, to be connected over an IP network so that end users may exchange voice communications via the connected CPE. Moreover, IP gateways have been developed that bridge IP networks with the Public Switch Telephone Network (PSTN), a circuit-switched network as opposed to a packet-switched network. That is to say, an IP gateway acts as a point of entry for IP calls into the PSTN, e.g., via a telephone switch, such as a class 5 switch, and vice versa for calls from the PSTN into the IP network.
Other types of real-time communications are also known which utilize an IP or other packet-switched network, e.g., Instant Messaging (IM). Via computers operatively connected to a common network (typically, the Internet), IM permits end users to exchange communications (e.g., text-based messages) with one another over that network in substantially real-time. Commonly, an IM client running on the end user's computer is employed to send and/or receive an IM message. In some cases, IM clients support a kind of presence detection so that end users connected to the network can detect the presence of other end users similarly connected to the network. In this manner, the end users are made aware of who is connected to the network and/or their availability for IM. Such presence detection often relies upon the end user being logged in or out of their IM client, the network, etc. This approach, however, can lead to unreliable detection of an end user's actual state of presence at their computer, e.g., when an end user forgets to log in or out so as to appropriately reflect their actual state of presence at their computer.
Furthermore, the concept of presence detection has not heretofore been suitably extended to IP telephony. Nevertheless, the suitable application of presence detection to IP telephony achieves, in certain instances, desirable results, the benefits and/or advantages of which have not been previously realized.
Accordingly, a new and improved approach to presence detection is disclosed that overcomes the above-referenced problems and others.